Raman scattering study on vibrational modes has been reported in ferromagnetic semiconductor Ga 1-x Mn x Sb grown by Mn ions implantation, deposition, and postannealing. The Raman experiments are performed in the implanted and unimplanted regions of the sample before and after etching. Only GaSb-like phonon modes are observed in the spectra measured from the unimplanted region. However, in addition to GaSb-like phonons, some extra modes are observed in the spectra measured from the implanted region of the sample. The experimental results demonstrate that the 115, 152, and 437 cm -1 modes are appeared due to surface defects and crystal disorder caused by Mn ions implantation and deposition processes. The origin of the weak structure observed approximately at 269 cm -1 is not so clear. However, the frequency position of MnSb-like LO phonon mode (266.4 cm -1 ) determined by reduced-mass model is found to be close to the experimentally observed mode at 269 cm -1 . The phonon mode appeared approximately at 659 cm -1 is found to be associated with blackish layer formed on the surface of the sample from the annealing process and is assigned to Mn 3 O 4 -like. Furthermore, existence of coupled LO-phonon plasmon mode is found in the spectra measured from the implanted and close to the implanted regions of the sample.

Raman scattering determination of hole density has been reported in diluted magnetic semiconductor Ga 1-x Mn x Sb prepared by Mn ions implantation, deposition, and post annealing. The Raman spectra measured from the implanted region of the sample show coupled plasmon LOphonon mode (CPLOM), which is found to be superimposed with GaSb-like phonon modes in the spectra. The spectral lineshapes are modeled using a dielectric function where interband and intraband transitions of free holes are included. In addition to CPLOM, the individual contribution arises from GaSb-like phonon modes are taken into account in the model. The hole density as a function of laser probing position is determined from the best fit parameters and is found to be in reasonable agreement with the results obtained from the electrochemical capacitance-voltage technique. Furthermore, the dependence of optical mobility, depletion width, and peak frequency of CPLOM with hole density is determined.